Had the collar for a year, and was very annoyed with how delayed their response is for when a dog leaves a safety zone. The GPS also didn't work correctly for one of the dogs and kept going off when she was in the backyard. They also came out with a new collar right after we purchased ours, and offered to trade them in but we would have still ended up paying full price. Very irritating overall, even if it was fun at the beginning. Both collars also broke within a week of getting wet (dogs splashed in a small kiddie pool and the collars were never fully submerged) despite saying they are waterproof.